KUALA LUMPUR - Former Malaysia prime minister Tun Mahathir Mohamad and his wife have returned two awards they received from the Selangor palace, an aide to the politician said on Monday (Dec 11), in an escalating tiff with the state ruler.

Selangor's Sultan Sharafuddin Idris Shah, who celebrated his 72nd birthday on Monday, has been unhappy with remarks made by Dr Mahathir labelling the Bugis people as "pirates" when he was attacking Prime Minister Najib Razak.

This is because the Selangor ruler's family also has Bugis roots.

Dr Mahathir made the remarks in October when he was attacking Datuk Seri Najib over the alleged theft of public money from state fund 1Malaysia Development Berhad (1MDB).

Dr Mahathir received the Selangor awards in 1978 and 2003, The Malaysian Insight news site reported on Monday. He is today leading the opposition Pakatan Harapan alliance.

The awards were reportedly returned to a senior officer of the Selangor palace in the Selangor capital of Shah Alam.

Sultan Sharafuddin is also in a separate tiff with another opposition leader, Datuk Zaid Ibrahim, over remarks that the ruler made over raising sensitive issues by politicians.

The direct entanglement of a Malaysian ruler, from one of the nine Malay royal houses, with politicians is quite unusual in the country where the ceremonial rulers usually stay above the political fray.

Dr Mahathir in one of his regular attacks against Datuk Seri Najib had reportedly said: "Maybe he (Mr Najib) can trace his ancestry to Bugis pirates. Somehow, he lost his way and came to Malaysia. Go home to Bugis!".

The Bugis people originated from what is today Indonesia's South Sulawesi province.

Sultan Sharafuddin in returning fire over the comments, said in a statement on Nov 2 issued by his royal council that Dr Mahathir had "clearly insulted and bracketed the Bugis as a people who originated from pirates, robbers and criminals".

He said: "The members of the Selangor Royal Council believe the speech was very extreme and could incite feelings of hatred and a negative perception of the Bugis people to the extent of causing disorder.

"This allegation indirectly insulted the ancestral roots of the Selangor sultanate which was founded by the Bugis."

Johor's Sultan Ibrahim Sultan Iskandar in late Novermber also said he felt slighted by Dr Mahathir's remarks. "I am of Bugis descent. The Sultan of Selangor is of Bugis descent. Many Johoreans are of Bugis descent. My ancestry can be traced to Riau-Lingga, where there are many Bugis people. What will the Bugis feel?"

"Imagine if I say that Chinese were robbers. Won't the Chinese feel slighted? If I say the Indians are murderers? The Indians will feel slighted," he told News Straits Times in an interview.

On the friction between Selangor's Sultan Sharafuddin's and Mr Zaid, a prominent member of the opposition Democratic Action Party, the ruler had on Dec 4 warned against the use of sensitive issues to fish for votes.

The Sultan said in an interview with The Star newspaper that he did not wish to see politicians playing with matters of race, religion and other sensitive issues.

"This is the concern of all the Malay Rulers, all nine of us. We have often discussed this during the pre-council meetings that we hold before the Conference of Rulers.

"The Rulers are very worried. Too many sensitive issues have been exploited for personal gain. Issues like these spread very fast on social media and it can divide our rakyat," said Sultan Sharafuddin.

Mr Zaid replied in a tweet on Dec 6 that the ruler should be "careful" with his words and that everyone would be affected if "the country burns".

Sultan Sharafuddin told Utusan Malaysia in an interview the next day that he was saddened by comments made by Mr Zaid, who is from Kelantan state.

"I ask Zaid Ibrahim to read my statement carefully and get the facts rights before opening his mouth," he was quoted as saying.

"He lives in Selangor, but he can go back to Kelantan if he does not agree, build a big house and help the Kelantan people. Do not look for sustenance in Selangor."

On Sunday, several thousand people led by Umno members gathered in Shah Alam to support the ruler and protest against remarks made by Dr Mahathir and Mr Zaid.